1. Technical Background
The present invention relates generally to medical devices, and more particularly to a vascular medical device.
2. Discussion
Vascular filters may be used for a variety of therapeutic applications, including implantable vena cava filters for capturing thrombus, or for distal protection during a vascular procedure.
Numerous different vascular filters are known of various types and designs. Prior filters are generally designed for either temporary use, such as may be provided on a catheter or provided with a mechanism for retrieving the filter, or for permanent implantation. Either a permanent or a temporary filter maybe preferred for a specific situation, given the specific therapeutic conditions and the properties of the filter.
The present invention relates to a filter system including a vascular filter that can be placed inside a body passage or cavity, such as a blood vessel, through a catheter consisting of a tubular basic body with a distal end, a proximal end and a catheter lumen extending in between the ends. The vascular filter can be received in a compressed state inside the catheter lumen, and the catheter is provided with an ejection device which can be used to eject the vascular filter from the distal end of the catheter.
Vascular filters of the type that are implanted in a patient's body vessel are often made of an elastic or so-called "memory" material. The vascular filter is positioned by using an ejection member to push the filter from the open distal tip of the catheter into the blood vessel.
Many prior vascular filters expand resiliently from the compressed state inside the catheter lumen to an enlarged or deployed state, when released or deployed at the desired site for treatment.
However, it is desirable to provide a filter capable of being implanted for a selectively variable duration. For example, a vascular filter according to the present invention might have a design such that the filter is deployed through a catheter, and then the filter may be transformed at a selected time later to provide an open "through lumen".
The present invention provides a novel vascular filter having a hybrid configuration, which is capable of being transformed to provide a through lumen at a time selected later.
Accordingly, it is desirable to provide a vascular filter capable of being implanted in an initial "filtering" configuration. The device may be monitored periodically for a time, until the physician decides to convert the implanted filter into a stent, for example. The filter is thus designed to selectively metamorphose into a second stent or graft configuration, providing a resilient tubular scaffold having and tending to maintain an open lumen through the body passageway.
Of course, the present invention relates broadly to vascular filters that are convertible into an open lumen device. The present invention may therefore be practiced in a multitude of different designs and variations which will occur to an average practitioner in the art.
These and various other objects, advantages and features of the invention will become apparent from the following description and claims, when considered in conjunction with the appended drawings.